Guide-free overhead door



May 1954 E. s. MONAGHAN ET AL 2,579,290

GUIDE-FREE OVERHEAD DOOR Filed 00tl, 1952 E2122 izsalz HZ fHE PatentedMay 25, 1954 UNITED S'i'dfTiiiid iE ATENT OFFICE Chicago, 111.; saidFrit Monaghan sch assignor to said Application October 1, 1952, SerialNo. 312,426

9 Claims.

The present invention relates to overhead doors. More particularly, theinvention concerns the construction of an overhead door of the typewhich may be folded or collapsed com pletely out of the way when in theopen position.

I The most common type of overhead door in commercial use todaycomprises the type in which the door runs along side guide rails. Theserails are extended upwardly and backwardly overhead so that when thedoor is opened, or pushed upwardly out of the way, it rolls along theguide rails into a position generally parallel to the floor and usuallya foot or two above the top level of the door opening. Other types ofoverhead doors now in general use utilize a solid one-piece door whichis counterbalanced so as to pivot approximately about its centerposition and then elevates to an overhead position approximatelyequivalent to that of the door utilizing the overhead rails abovediscussed.

It is found in the use of overhead doors for trucking terminals andother establishments utilizing loading docks, that the above mentionedcommercial doors are entirely unsatisfactory. This is true since therails and guides utilized with the doors and the position of the dooritself blocks the free movement of loading and unload ing equipment.Recent developments in material handling have made the use of the socalled pallets practically universal. Under this system, goods arestacked upon a wooden platform or pallet which is readily picked up bysmall vehicular loading cranes or lift trucks having lift forksprojecting from the front thereof. Through the use of the combination ofthe pallet and the lift truck it is now possible, and is indeeddesirable, to move much merchandise in very tall stacks, a featheretofore impractical.

In practice, therefore, the stacks of goods being carried by the lifttrucks is very often higher than the guide rails and other paraphernaliautilized with the prior art overhead doors. This has resulted in greatdamage to such door guideways and in some instances has lead to injuriesdue to the guide rails being dislocated upon accidental impact thereuponby stacks of moving material with the result that the overhead doorsupported thereby has fallen upon persons be low. A further source oftrouble has been the presence of the relatively fragile guideways at thesides of the door aperture. In practice, these guides are repeatedlydamaged by the lift trucks and other equipment necessitating constantand expensive maintenance. In order to eliminate these causes ofdifficulty, it is an object of the 2 present invention to provide anoverhead door which may be withdrawn completely from the area formerlyoccupied by overhead sliding doors.

A further object of the present invention is the provision of anoverhead folding door which requires no guideway whatever and which hasall of its working parts mounted on the door structure therebypreventing injury thereto by loading equipment.

Yet another object of the present invention is the, provision of asimple overhead door having a construction which seals the openingagainst all types of weather and in which the sealing mechanism is notsubject to injury by loading equipment of the type which is in commonuse.

Still another object of the present invention is the provision of acounterbalanced overhead folding door which may be readily operated byonly a slight pressure of the hand.

Still another object of the present invention is the provision of anoverhead folding door which may be folded down into a closed positionand maintained in said closed position by latch means the movable partsof which are all mounted on the door members rather than the door frame.

Yet another object of the present invention is the provision of anextremely simple, counterbalanced overhead door requiring no overheadguides, side guideways or other similar constructions for guidingmovement thereof into the open position.

A feature of the present invention is the provision of a spring biaslinkage which simultaneously moves the door member to an overheadposition and also pulls it into a compact folded relationship.

Another feature of the present invention is the elimination of guideframes of any sort.

Yet another feature of the present invention is the provision ofassembled door latching means having all of its moving parts positionedonthe door panel itself thereby preventing the possibility of injury ofthe door latch by machinery, utiized during the time in which the dooris in its open, folded position. 7

Other and further objects of the present invention will become apparentto those skilled in the art upon consideration of the accompanying sheetof drawings taken in connection with the following description thereof.

On the drawings:

Figure 1 is a front elevational view showing a two-panel folding doorconstructed according-to he present invention.

Figure 2 is a side elevational view of the door construction shown inFigure 1 and taken from the right hand side of Figure 1.

Figure 3 is an enlarged partial view of the linkage utilized in foldingthe doors of the present invention.

Figure 4 is a partial cross sectional view showing a modification of thedoor latch utilized with the bottom of the door for maintaining it in aclosed position.

As shown on the drawings:

As may be clearly seen from Figure l the folding door of the presentinvention comprises a pair of door panels I and 2. The uppermost panel Iis hinge .ly secured by means of hinges 3 to the upper edge of a dooropening 4. The door panels I and 2 are hingedly secured to each other bymeans of the hinge member 5 which may, as in the case of the hinge 3,comprise any of the standard known types of hinges such as the pianohinge or a plurality of butt hinges. As may clearly be seen from Figure3, the hinge between the panels I and 2 is a weather proof hinge havinginterlocking members (i and 'l which bafiie the opening therebetweenwhen the door is in its closed, extended position.

Counterhalancing mechanism is provided for aiding in the lifting of thedoor into its folded, open position. This counterbalancing mechanismcomprises a spring actuating means generally indicated at ill and havinga pulley H which is actuated in the counterclockwise direction as shownin Figure 2 by means of a torsional spring 12 which is fixed at itsright hand end l2a and secured at its left hand end to the drum l3 bymeans of the offset spring end H1). The pulley H and the drum K5 arefixedly secured to the shaft M which is rotatably mounted in the supportbracket IS. A wire cable It is coiled about the pulley ll, stud H whichforms the pivot for the links 16 and IS. The links l8 and H] arepivotally secured at their outer ends to the door panels I and 2 bymeans of brackets 20 and 2|. As may be seen from Figure 2, the links [8and I!) assume a position somewhat less than straight out when the dooris in its closed position.

In order to prevent the links from opening outwardly rather thaninwardly as desired, we have provided stops 22 integral with the ends ofthe links 18 and IQ for preventing the links I8 and I9 from snappingover center. It should be noted also that the links are prevented fromaccidental pivotal movement over-center by the latch bolt constructionwhich will be described later.

It will further be understood that the space required to accommodate thelinkage as viewed from Figure 1 is exaggerated to aid in the disclosure.This gap between the door and the side wall will. of course, be muchless, in a relative sense, in the actual construction.

Due to the placement of the spring. pulley H as shown in Figures 1 and2, the lever arm upon which the spring force acts. is decreased as thedoor isv moved toward its. closed or extended position. This compensatesfor the fact that the spring is increasingly tensioned as the doors arebrought downwardly into their closed position thereby providing asubstantially constant spring counterbalancing force up to the pointwhere the doors are substantially fully closed and the links l8 and I9are practically fully extended, at which time there is practically noforce tending to open the door, and the force that is presand isattached to a ent is overcome easily by the weight of the doorsthemselves.

It will be further noted that while the spring arrangement shown at it)in Figures 1 and 2 has proved very satisfactory, various otherconstructions may be equally effective. For example, in installationswhere the height of the ceiling is greater than the height of the dooropening by a distance equal to or greater than the width of the doorpanels, it is desirable to incorporate spring means that will notinterfere with folding the panels flat against the wall above the door.It is contemplated that in such installation the spring mechanism hereshown at 1B, which is the standard spring now in use with the commonguided type of door and which may be retained during replacement by adoor of this invention, be reversed thereby placing the mounts l5 in thespace at the side of the door. This positioning removes the springmechanism from its position between the door panel I and the wall. Inmultiple-door buildings there is generally suflicient space between thedoors to accommodate the length of the spring mechanism It.

A further spring arrangement which is available during construction ofthe building, is the embedding of the spring mechanism in a recess inthe wall. In such an installation the cable It would be entrained aboutthe pulley H counterclockwise as viewed in Figure 2 in order to positionit along the wall in generally the same position it occupies in Figure 2of the drawings.

In order to permit easy opening and closing of the doors we haveprovided the handles 25 and 26. While these handles may, of course, beplaced at any convenient position on the door, we have found that theposition indicated, which places the handles about a third of the wayfrom the center hinge 5 to the outer edges of the panel, is verysatisfactory and places the handle at a convenient height for operation.With the handles in these positions, the operator may reach them withoutbending over and since the doors are counterbalanced, only a littleeffort is needed in actuation of the doors, thereby eliminating thenecessity of placing the handles at the outer extremity of the doorpanel. Since the doors fold into a position which is high overhead, itis also usually convenient to provide a pull rope such as that shown at21. This rope is preferably of a short length, sufficient only to placeit within reach of the outstretched hand of the operator, therebyplacing it out of usual contact with material or persons passing.through the door.

Latching means are provided at 36 for maintaining the door in its closedposition. This latching construction comprises a pair of reciprocatablebolts 31 and 32 which are carried for sliding movement by the guides 33.The bolts are ivotally connected to the links 34 and 35 which are inturn pivotally connected to the bar 36 which is. mounted for rotation onthe doorpanel I. A handle 31 is provided for oscillating the link 36 tothereby reciprocate the bolts SI and 32. The bolts coact with U-strapsor apertures 38 and 39 in the building wall. When the handle 31 isoscillated in the counterclockwise direction the bolts are reciprocatedoutwardly into engagement with the members 38 and 39- thereby securelylooking the door.

It is, of course, understood that various forms of locking means couldbe utilized in the present invention and we have shown merely anillustrative type which has important advantages. In the first place allof the moving parts of the lock construction herein shown are mounted onthe door members themselves. This is extremely important ininstallations of the present type, since the door members and lock partsare pivotally moved out of all danger from moving trucks, hoists andother heavy machinery which are manipulated in the vicinity of the sidesof the door openings, thereby preventing any damage from occurring tothese rather expensive and hard to to replace parts.

An alternative type of latch which meets the requirement of all movingparts on the door panels is the cam-locking type. In such a constructiona rotary bar having radially extending cam cars is mounted in the doorpanel near the edge thereof. The frame member 9 is provided with a borefacing the door and in alignment with the of the rotary bar. The borehas radial slots at its edges for allowing passage of the bar with itscam cars.

In operation the door panels are held flat against the members 9 and therotary bar is rotated until the cam ears align themselves with theradial slots, at which time the bar passes into the member 5. Cam facesare provided in the bore so that rotation of the bar after passing intothe member 9 will cause the cam ears to engage the cam faces to hold thedoor and frame locked together in much the same manner used withautomotive radiator caps.

In this arrangement the only latch part found on the wall is theaperture in the frame member 9, thereby making it practically impossibleto in-- iure the working parts of the latch by impact of moving lifttrucks or other impl ments.

Several alternatives are posible in latching the bottom of the doorclosed and by way of illustrative example we have shown two preferredconstructions. As shown in Figures 1 and 2, we have provided L-shapeddoor retainer brackets 36. These are embedded in the walls or floor ofthe building or in the side posts 9, and extend a short distance abovethe floor level. Since the folding door the present invention permitsthe bottom panel to travel in almost a straight upward direction uponrelease of the door from its closed position, the panel 2 is permittedto move upwardly and out of engagement with the L brackets it. However,when the door is in its closed position and latched by the latch bolts3! and the bottom panel 2 is absolutely prevented from any movement bythe upwardly extending arm of the L bracket.

A second modification of the door latch for use with the door panel 2 isshown in Figure 4. In this figure the panel 2 has firmly aflixed theretoa pointed bolt ti. This bolt cooperates with the socket 422 in the floorof the building when the door panel 2 is moved into the door closedposition. It is apparent that this bolt and socket arrangement willprevent any movement of the panel 2 parallel to the floor when the dooris in its closed position and latched by means of the latching mechanism3E1.

Both of the latching means 4t and G! are extremely simple and are alsoplaced in out-of the-way spots so that little danger exists of injuringthem by passing vehicles, etc. This is, of course, particularly true ofthe construction shown in Figure 4 wherein no projecting parts whateverare found on the floor or framework of the building, the bolt 4! beingplaced upon the 6. door panel 2 which is, as is shown in the dottedlines of Figure 2 folded into a position entirely out of the way ofpassing objects.

It will be readily apparent that the door of our construction is veryeasily sealed against draft and other heat losses. By utilizing weatherstripping at 43 between the panels i and 2 and the side post 3, and byalso utilizing a common rubber flap 44 at the bottom edge of the doorpanel 2, it is possible to completely seal the door opening when thedoor is in the closed position. As explained before, the bafile hingearrangement at E, i prevents the leakage of air through the hinge 5.

is noted also that in accordance with the fundamental concept ofmaintaining the doorway free of damageable parts, it is preferred thatthe weatl'ierstripping Z3 be placed on the panels I and 2, rather thanon the members 9, although either position can of course be used.

It will be further readily apparent to those skilled in the that thedoor construction of the present invention has eliminated the majordifficulties encountered with the present overhead doors by firstcompletely eliminating all guide rails, both overhead and along thesides of the door opening, thereby eliminating interference of theseparts with material handling equipment or other objects passing throughthe door aperture and also e minating to such parts; second, byproviding an easily sealed door which is superior in heat retention todoors utilizing guide rails and, thirdly, by providing a completelycounterbalanced and very easily moved door which requires only a minimumamount of effort to open or close, the frictional losses beingmaintained at a minimum which is substantially less than those found indoors utilizing the guide c0nstruction.

It will be understood that modifications and variations may be effectedwithout departing from the scope of the novel concepts of the pr sentinvention.

We claim as our invention:

1. An overhead door comprising a pair of door panels hingedly secured toeach other along a -orizontally disposed edge, the upper panel beinghingedly secured to the top edge of a door frame, linkage meansassociated with said panels and comprising a first link pivoted to avertical edge of said upper panel and a second link pivotally secured toa vertical edge of the lower panel, said first and second links beingpivotally secured to each other at their free ends by means of a stud,means applying an upwardly directed force to the stud whereby the weightof said door is counterbalanced and whereby the upper and lower panelsmay be folded against each other and about the said top edge into afolded overhead position.

2. A weather-proof overhead door comprising first and second door panelspositioned edge to edge one over the other, hinge means securing saidpanels together along horizontally disposed abutting edges, second hingemeans for securing the first panel to the upper edge of a, door frame,counterbalancing means for counterbalancing the weight of said doorpanels comprising first link means pivot-ally secured to a vertical edgeof said first panel, second link means pivotally secured to acorresponding vertical edge of said second panel, pivotal fasteningmeans connecting the other ends of said first and second links to eachother at a point substantially coaxial with the axis of said first hingewhen said panels are in the door-closed position, and actuating meansacting on said fastening means to apply a force from an overheadposition thereto, said actuatin means cooperating with said link meansto slightly overbalance the weight of the door panels except when in thesubstantially door closed position.

3. In combination a four sided aperture defining frame, first hingemeans secured to the upper edge of said frame, a first door panelsecured to said hinge for pivotal movement about the top edge of saidaperture, a second panel hingedly secured to the bottom horizontal edgeof said first panel and adapted to pivot about said edge, sealing meanscarried by the bottom horizontal edge of said second panel forcooperation with the bottom edge of said frame, a pair of side postssecured to the side edges of said frame and having sealing meanspositioned along a vertical edge thereof facing said panels for sealingcooperation therewith when in closed position, counterbalaneing meanscomprising a first link pivotally secured to a vertical edge of saidfirst panel, a second link pivotally secured to a corresponding verticaledge of said second panel, connecting means pivotally securing saidlinks to each other, and force-applying means acting upwardly againstsaid connecting means, and latch means having all moving parts thereofmounted on one of said panels for positively retaining said door panelsin the closed extended position.

4. An overhead closure for use with loading platforms which comprises apair of panels disposed edge to edge, first hinge means securing one ofsaid panels to the upper edge of an aperture defining frame, secondhinge means securing said second panel to said first panel alongabutting horizontal edges of said panels, combined folding andcounterbalancing linkage for folding said panels upon each other and formaintaining said panels in an out-of-the-way overhead folded position,movable latch means mounted on one of said panels for cooperation withfixed latch means on the sides of said frame for maintaining said panelsin an extended closed position in said frame, and manual actuating meanson one of said panels for the application of an additionaloverba-lancing opening or closing force.

5. A folding overhead door comprising a pair of door panels, hinge meanssecuring said panels together at abutting horizontal edges, second hingemeans securing the upper of said panels to the top of a door frame andtoggle link means associated with said panels and actuatable upwardlyfor folding of said panels into an overhead position.

6. A folding overhead closure comprising a pair of panels, hinged meanssecuring said panels together at abutting horizontal edges, second hingemeans securing the upper of said panels to the top of a cl sure frame,and toggle link means associated with said panels and actuatableupwardly at the toggle pivot thereof for folding of said panels into anoverhead position outside of said frame.

7. A folding overhead door comprising a pair of door panels, first hingemeans securing the upper of said panels to the top of a door frame andtoggle link means associated with said panels and actuatable upwardlyfor folding of said panels into an overhead position, said toggle linkmeans comprising a first link pivoted to said upper panels and a secondlink pivoted to the other of said panels, and pivotal means securingsaid links together at the ends thereof remote from the panels, saidlinks and said pivot being foldable in a direction opposite to saidpanels.

8. Apparatus in accordance with claim 5 wherein actuating means areprovided for actuating the toggle upwardly toward a point above saidsecond hinge means.

9. Apparatus in accordance with claim 5 wherein movement of said doorinto said overhead position may be accomplished independ' ently of anyassociation with the vertical side walls of said door frame.

' References Cited in the file of this patent UNITED STATES PATENTSNumber Name Date 1,493,750 Holbrook May 13, 1924 1,733,694: Price Oct.29, 1929 2,090,099 Bittorf Aug. 17, 1937 2,201,636 Siess May 21, 19402,393,052 lviehard Jan. 15, 1946

